Cylinder block mounted two-pass oil cooler

ABSTRACT

A water-to-oil heat exchanger or cooler operates to cool oil contained within an engine having a cylinder block. The cooler is removably attached to the cylinder block such that oil is communicated directly from the cylinder block to the cooler and from the cooler to the cylinder block. The cooler has a two-pass architecture.

TECHNICAL FIELD

The present invention relates to oil coolers for a vehicular engine and more specifically to a two-pass oil cooler that is directly mounted to the cylinder case or block of the vehicular engine.

BACKGROUND OF THE INVENTION

Modern vehicular engines employ coolers or heat exchangers to cool the oil contained within the engine. It is important to maintain cool oil in order to retain the lubricating characteristics of the oil under severe operating conditions, such as high engine speed and high engine load. Oil coolers may be categorized into two main groups, air-to-oil and water-to-oil. With an air-to-oil cooler, the oil to be cooled passes through a series of tubes that commonly have fins attached thereto that operate to increase the surface area available to effect cooling. The air-to-oil cooler is then subject to a flow of air, such as from a fan or the “ram air” effect of the moving vehicle. As the air passes over the fins and tubes, the heat energy of the oil is extracted by the air stream through convection. Since a flow of air is required for the operation of the air-to-oil cooler, the air-to-oil coolers are typically remotely mounted with respect to the engine.

Alternately, with one variation of the water-to-oil cooler, the oil to be cooled passes over a first series of stacked plates while water or coolant from the engine passes over a second series of stacked plates, interleaved with the first series, such that heat transfer between the oil and coolant may occur. The oil-to-water cooler is typically very efficient and as such, may be made to occupy a smaller volume than the air-to-oil cooler. However, modern vehicle designs dictate tighter packaging requirements within the engine compartment of vehicles, thereby making remotely mounted oil-to-water coolers the norm.

SUMMARY OF THE INVENTION

Provided is an oil cooler for an engine having a cylinder block. The oil cooler has a base plate and at least one fastener operable to removably mount the base plate directly to the cylinder block of the engine. The cooler also includes a top plate. Additionally, a plurality of plates are disposed between the base plate and the top plate to form a two-pass cooler configuration. The base plate defines a first port and a second port. The first port operates to communicate oil from the cylinder block to the cooler and the second port operates to communicate oil from the cooler to the cylinder block. The top plate includes a first and second fitting attached thereto. The first fitting operates to communicate cooling fluid to the cooler and the second fitting operates to communicate cooling fluid away from the cooler.

The above features and advantages and other features and advantages of the present invention are readily apparent from the following detailed description of the best modes for carrying out the invention when taken in connection with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side elevational view of a portion of a vehicular transmission and engine, the engine has attached thereto a block mounted two-pass oil-to-water cooler consistent with the present invention;

FIG. 2 is front elevational view of the two-pass oil-to-water cooler shown in FIG. 1, illustrating the coolant inlet and coolant outlet configuration; and

FIG. 3 is a rear elevational view of the two-pass oil-to-water cooler shown in FIGS. 1 and 2, illustrating the oil inlet and oil outlet configuration.

DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring to the figures, wherein like reference numbers correspond to like components throughout the several views, there is shown in FIG. 1 a portion of a vehicular powertrain 10 having an engine 12 and a transmission 14. Removably mounted with respect to a cylinder case or block 15 of the engine 12 is an engine oil heat exchanger or cooler 16. The cooler 16 has a plate-type oil-to-water configuration wherein a plurality of channeled plates 18 are interleaved with one another and subsequently fastened by known methods, such as brazing. The internal structure of the cooler 16 allows coolant 17, shown in FIG. 2, and oil 19, shown in FIG. 3, to interact such that heat energy contained within the oil 19 is transferred to the coolant 17. Additionally, the cooler 16 is a two-pass type cooler. The two-pass architecture forces the oil 19 to pass twice over the plates 18, such that a greater amount of heat transfer occurs compared to a single pass cooler of similar size and construction. Additionally, the cooler 16, in the preferred embodiment will force the coolant 17 to pass twice over the plates 18 prior to exiting the cooler 16.

Referring now to FIG. 2, a front elevational view of the cooler 16 is presented further illustrating additional aspects of the cooler 16. The cooler 16 includes a base plate 20 and a top plate 22 with the plurality of plates 18 disposed therebetween. The base plate 20 operates to provide structure to the cooler 16 thereby facilitating the attachment of the cooler 16 to the cylinder block 15. The base plate 20 operates to isolate the stresses associated with fastening the cooler 16 to the cylinder block 15. The base plate 20 defines a plurality of bores 24, which are sufficiently configured to receive a fastener 26, such as a hex head bolt. Those skilled in the art will recognize other methods of fastening the base plate 20 to the cylinder block 15, such as stud and nut fastening techniques. Additionally, the base plate 20 further includes provisions to allow the flow of oil 19 into and out of the cooler 16. These provisions will be described hereinbelow, with reference to FIG. 3.

A generally tubular elbow fitting 28 is mounted with respect to the top plate 22 and operates to communicate a fluid, such as coolant 17 from the vehicle's cooling system, to the cooler 16. A second generally tubular elbow fitting 30 is mounted with respect to the top plate 22 and operates to communicate coolant 17 from the cooler 16 to the cooling system of the vehicle. Each of the fittings 28 and 30 are sufficiently configured to receive a hose member, not shown. A generally annular lip 32, 32′ is provided respectively on each of the fittings 28 and 30 to operate as a stop thereby limiting the engagement of the fittings 28 and 30 by the hose members, not shown. Additionally, a generally annular barb 34, 34′ is provided respectively on each of the fittings 28 and 30 and operate to retain the hose members, not shown, in relation to the fittings 28 and 30. Those skilled in the art will recognize that the fittings 28 and 30 may be oriented differently than those shown in FIG. 2 depending on the requirements of a given application of the cooler 16. Additionally, the two-pass configuration of the cooler 16 allows the fittings 28 and 30 to be provided on the top plate 22 substantially adjacent to each other thereby enabling tighter packaging. The arrows representing coolant 17 and oil 19 in FIG. 2 and FIG. 3, respectively, illustrate the two-pass nature of the cooler 16. The internal configuration of the cooler 16 will force the coolant 17 and 19 though only a portion of the cooler 16, thereby forcing the coolant 17 and the oil 19 to flow two times the length of the cooler 16.

Referring to FIG. 3, a rear elevational view of the cooler 16 is shown, illustrating various features of the base plate 20. The base plate 20 defines a first port 36 and a second port 38, which operate to communicate oil 19 into and out of the cooler 16, respectively. The base plate 20 has a generally circular groove or channel 40 formed therein. The channel 40 is operable to receive an elastomeric o-ring seal 42. Likewise, the base plate 20 has a generally circular groove or channel 44 formed therein and operates to receive an elastomeric o-ring or seal 46. The seals 42 and 46 operate to disallow leakage of oil 19 from between the cylinder block 15 and the cooler 16. Those skilled in the art will recognize that other sealing methods may be employed in lieu of seals 42 and 46, such as room temperature vulcanizing (RTV) sealant, captured gasketing, etc. In operation, the oil 19 will pass from a predetermined oil passage 48, defined by the cylinder block 15, directly into the cooler through port 36. After being cooled, the oil 19 from within the cooler 16 will then exit the cooler through port 38 and pass back into another predetermined oil passage 48′ defined by the cylinder block 15.

By directly mounting the cooler 16 to the cylinder block 15, the additional hoses and clamping members required to communicate oil 19 to a remotely mounted cooler are greatly reduced. Additionally, by providing the compact cooler 16 with a two-pass architecture the volume or spatial envelope required to package the cooler 16 is reduced as compared to the much larger single-pass cooler required to achieve similar heat rejection capabilities for a given oil pressure drop across the cooler.

While the best modes for carrying out the invention have been described in detail, those familiar with the art to which this invention relates will recognize various alternative designs and embodiments for practicing the invention within the scope of the appended claims. 

1. An engine comprising: a cylinder block defining a first oil passage and a second oil passage; a stacked plate oil cooler removably mounted directly to said cylinder block, said stacked plate oil cooler being in direct fluid communication said first and second oil passage; wherein said stacked plate oil cooler is operable to receive oil directly from said first oil passage and said stacked plate oil cooler is operable to communicate said oil directly to said second passage; wherein said stacked plate oil cooler operates to transfer heat energy from said oil within said stacked plate oil cooler to a cooling fluid within said stacked plate oil cooler; and wherein said stacked plate oil cooler has a two-pass configuration.
 2. The engine of claim 1, wherein said stacked plate oil cooler includes a base plate, said base plate being operable to removably mount said stacked plate oil cooler directly to said cylinder block.
 3. The engine of claim 2, wherein said base plate defines a first port and a second port, said first port being operable to communicate oil from said first oil passage to said stacked plate oil cooler and said second port being operable to communicate oil from said stacked plate oil cooler to said second passage.
 4. The engine of claim 3, wherein said first and second ports are sealed with elastomeric o-rings.
 5. The engine of claim 1, wherein said stacked plate oil cooler further includes a top plate having a first and second fitting attached thereto, said first fitting being operable to communicate said cooling fluid to said stacked plate oil cooler and said second fitting being operable to communicate said cooling fluid away from said stacked plate oil cooler.
 6. The engine of claim 1, wherein said stacked plate oil cooler is removably mounted to said cylinder block by a plurality of fasteners.
 7. An oil cooler for an engine having a cylinder block, the oil cooler comprising: a base plate; at least one fastener operable to removably mount said base plate directly to the cylinder block of the engine; a top plate; and a plurality of plates disposed between said base plate and said top plate, said plurality of plates forming a multiple pass cooler configuration.
 8. The oil cooler of claim 7, wherein said base plate defines a first port and a second port, said first port being operable to communicate oil from the cylinder block to said cooler and said second port being operable to communicate oil from said cooler to the cylinder block.
 9. The oil cooler of claim 8, wherein said first and second ports are sealed with elastomeric o-rings.
 10. The oil cooler of claim 7, wherein said top plate includes a first and second fitting attached thereto, said first fitting being operable to communicate cooling fluid to said cooler and said second fitting being operable to communicate cooling fluid away from said cooler.
 11. An oil cooler for an engine having a cylinder block, the oil cooler comprising: a base plate; at least one fastener operable to removably mount said base plate directly to the cylinder block of the engine; a top plate; a plurality of plates disposed between said base plate and said top plate, said plurality of plates forming a two-pass cooler configuration; wherein said base plate defines a first port and a second port, said first port being operable to communicate oil directly from the cylinder block to said cooler and said second port being operable to communicate said oil directly from said cooler to the cylinder block; and wherein said top plate includes a first and second fitting attached thereto, said first fitting being operable to communicate cooling fluid to said cooler and said second fitting being operable to communicate said cooling fluid away from said cooler.
 12. The cooler of claim 11, wherein said first and second ports are sealed with elastomeric o-rings. 